Science exploration and instrumentation of the OKEANOS mission to a Jupiter Trojan asteroid using the solar power sail

Abstract An engineering mission OKEANOS to explore a Jupiter Trojan asteroid, using a Solar Power Sail is currently under study. After a decade-long cruise, it will rendezvous with the target asteroid, conduct global mapping of the asteroid from the spacecraft, and in situ measurements on the surface, using a lander. Science goals and enabling instruments of the mission are introduced, as the results of the joint study between the scientists and engineers from Japan and Europe.